Motor operator



July 1o, 1945. w. E. EDELMAN 2,379,954

MOTOR OPERATOR Filed March 2, 1942 4 Sheets-Sheet 1 Fig 96H2 Z4 6 H3107 1 AuToMATc 4 CLOSED NVPNTOR.

Waler E. Ede lman By M July 10, 1945. W- E' EDEl-MAN 2,379,954

MOTOR OPERATOR Filed March 2, 1942 4 Sheets-Sheet 2 O g [52 [53 [54 o ya@ 7 [9E/' Fgl '35 AuToMArlc lo OPEN Lesen -13/ 93 /o/ /17 /16 WalerEEdeLman NW9/.Mw

INV ENTOR.

July 10, 1945. w. E. EDI-:LMAN

MOTOR lOPERATOR 4 Sheets-Sheet 5 Filed March 2, 1942 I ldlllllllll Il II INVENTOR. BY Wal'er E.E'celman `M w. Mw

July 10, 1945. w. E. EDELMAN 2,379,954

MOTOR OEERATOR Filed Maron l2, 1942 4 sheets-sheet 4 Patented July 10, 1945 2,379,954 MOTOR OPERATOR Walter E. Edelman, Minneapolis, Minn., assigner to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation of Delaware Application March 2, 194,2, Serial No. 432,968

(Cl. v17 2-36) 12 Claims.

This invention relates to motor operators for controlling dampers, Valves, 'and the like devices, such as might be used in connection with air, steam, water, oil, and gas heating systems.

An object of the invention, generally, is to provide improvements in the details of construction and arrangement of parts of motor operators of this type.

Another object is to provide a motor operator of the type described having a minimum number of parts which readily may be assembled, and Which may conveniently be disassembled for purposes of inspection and repair.

A further object of this invention is to provide a, motor operator having a casing comprising a xed and a removable portion, the fixed portion of which has means for mounting the same on a suitable support, such as a vertical wall, beam, or the like, and the removable portion of which serves as a mounting base for the operating and control parts of the motor operator, whereby the removable casing portion together with the operating and control parts may .be removed from the xed casing portion without necessitating the severance of electrical connections, disassembly of operating parts, or removal of the xed casing portion from its operative position.

It is a further object of this invention to provide a motor operator having a casing comprising a fixed and a removable portion in which the removable portion serves as a mounting base for the operating and control parts, including a panel, of the motor operator, and in which a part of the i'lxed casing portion is shaped so as to interttingly receive the panel whereby the panel is readily accessible for making external electrical connections therewith and is conveniently removable from the Xed casing portion together with the removable casing portion without necessitating the severance of either external or internal electrical connections therewith.

A further object of this invention, in which a motor Operator is provided having a casing comprising a nxed and removable portion, is to utilise each casing portion as a, journal for the operating shaft of the motor operator, the operating shai't extending beyond the casing portions, but being removable from the fixed casing portion together with the removable casing portion and the other motor operator parts, including the panel, supported thereon.

An additional object of this invention is to provide improvements in the details of construction of operator arms for operating shafts which may be removably, but securely, mounted thereon.

Another object is to provide, in a. motor Operator of the type described, means whereby the ends of the motor windings may be secured to convenient parts of the motor and fastened directly to the panel thereby providing a motor operator requiring but a, minimum number of internal connections to effect its operation for the purposes intended.

Other objects are to provide, in a motor operator of the type described, novel combinations and arrangements of the switch means and actuating means therefor whereby a plurality of s such switch means may be depended from a single panel and actuated by a single element carried by the operator shaft thereby providing a compact assembly occupying but a minimum of space.

Still other objects are to provide, in a motor operator of the type described, novel combinations of switch means and acuating parts therefor which are secured thereto in a simple and expeditious manner.

Still further objects are those implied or inherent in all other combinations, constructions, and arrangements of parts hereinafter specically illustrated, described, and claimed, reference being had to the accompanying drawings in which Figure l is a, sectional view 0f the motor operator as viewed along the lines I--i of Figure 2, looking in the direction of the arrows,

Figure 2 is a view of the motor operator as viewed from a, position beneath the same as shown mounted on a vertical wall in Figure l,

Figure 3 is an inside view of the fixed portion of the motor operator casing,

Figure 4 is an inside view of the removable portion of the motor operator casing showing the operator parts supported thereon, the motor being removed to ,better illustrate the remaining parts,

Figure 5 is a view of an operator arm as viewed along the lines 5--5 of Figure 2, looking in the direction of the arrows,

Figure 6 illustrates the details of construction of the switch blades,

Figure 7 is an inside view of the panel assembly, certain parts being broken away for greater clarity,

Figure 8 is a View of a winding insulation piece shown as viewed along the lines 8-8 of Figure l,

Figure 9 is a schematic view of a control circuit for a, heating system which utilizes the motor operator as a, part thereof,

Figure 10 is an outside View of a modified panel assembly,

Figure 11 is an inside view of the modified panel,

Figure 12 is an elevational View of the modified panel,

Figure 13 is a schematic view of a condition control system which utilizes the modified form of the motor operator as a part thereof.

Figure 14 is an elevational view of the motor,.

showing parts associated therewith, of the improved device,

Figure 15 is a sectional view taken on line ||5 of Figure 14, looking in the direction indicated by the arrows, and

Figure 16 is an elevational view of the panel assembly of the embodiment shown in Figures 1A.

Referring to Figures l to 9, the numeral 2|] generally designates a motor operator which in Figures l and 3 is shown mounted on a vertical wall by means of suitable screws 2| The screws 2| are received in apertured ears 22 which are formed integrally with the motor operator casing generally designated bythe numeral 23. The motor operator is mounted approximately at eye level in which position it appears as shown in Figure 1. In this position a manual control lever 24 conveniently may be` adjusted in accordance withV the legends inscribed upon a plate 25, as shown in Figure 2, wherein the motor operf ator appears as viewed from a position beneath the same as shown in Figure l.

The casing 23 comprises a generally box-shaped portion 26, and a cover portion 21 removably secured thereto by means of screws 28, 29. The screws 28 extend through apertured bosses 3U formed integrally with the-cover portion 21 and are received into threaded apertures provided in bosses 3| formed integrally with the casing portion 26 and extended the full depth thereof. Screws 29 similarly enter apertures 32 formed in the base of the cover portion 21 `and are received into threaded apertures 33 provided in the base of the casing portion 28. It here should be pointed out that the mounting ears 22 are formed integrally with the casing portion 26, and that the control and operating parts of the motor operator are supported entirely by the cover portion 21 as hereinafter to be described. Thus, the cover portion 21 may be removed from the casing portion 26 which remains in its mounted position as shown in Figure 3. The inside of the cover portion together with the parts supported thereon then appears as shown in Figure 4. In this figure, however; the motor-hasbeen `omitted to better illustrate the other parts. Accordingly, hereinafter the casing portion 26 will be referred to as the fixed casing portion, and. the cover portion 21 will be referred to as the removable oasing portion.

The casing portions 2E, 21 each have pressed therein a sleeve bearing 31|,` 35 respectively. To insure alignment of the bearings 34, 35 and to facilitate the ease of assembly of the casing portions 26, 21, a flange 36 is formed integrally with the removable casing portion 21 which extends into the fixed casing portion 26 as best shown in Figure 1.

An operating shaft 31 is journalled in the bearings 34, 35 and projects beyond them on each side of the casing, each projecting end of the shaft having a squared portion 38, 39 for receiving an operating arm 4|), 4| respectively.`

Arms 40, 4| may be identical, each being substantially J shaped and having a pair of aligned apertures 42 formed therein for receiving the squared portions of the shaft 31, the apertures for this purpose being squared as shown in Figure 5. The apertures 42 are elongated to each side thereof forming `a slot 43 which extends through the bight portion of the arm thereby bifurcating the arm and providing furcations 44 and 45 which may be drawn together to clamp the'arm to the shaft. For this purpose a machine screw 46 is used which extends along the bight portion of the arm between the same and the shaft. The screw Carries a nut 41 seated in an indentation 48 which serves to hold` the same in non-turnable'relation with respect to the arm and a washer 49 similarly seated in an indentation 50 which serves to center the screw 45 between the shaft and the bight portion of the arm.

From the foregoing it is obvious that I have provided a novel7 simple,`andextremely effective means for removably securing the operating arm of a motor operator to its shaft since the squared shaft portion and cooperating squared apertures in the arm not only provide a mutual locking engagement but the provision of the clamping means serves to prevent all possibility of relative rotation between them as well as serves to hold the arm against axial movement with respect to the shaft.

Operating shaft 31 carries a gear 5| which is suitably'mounted thereon for rotation therewith. Shaft 31 is driven by a motor generally designated 52 through a suitable gear train generally indicated by the numeral 53 of which a pinion 54 operatively makes engagement with the gear 5|, as shown in Figure 4. Ihe gear train 53 is mounted for rotation between the removable casing portion 21 and a plate `55 supported thereon, being journalled therebetween in any suitable manner. In the arrangement shown in Figure 4, the several gears comprising the gear train 53 are separately mounted for rotation on pins 56 which on one end are staked to the plate and on the other end are received in suitable sockets, not shown, provided in the removable casing portion 21.

The motor 52 is conveniently mounted on the plate 55 by means of suitable screws 51 in such a manner that a pinion 58 secured to the motor shaft 59 extends through an aperture Soin the plate 55 to operatively engage a first gear 6| of 'the gear train 53.

The plate 55 is supported on three posts 62 formed integrally with the removable casing portion 21, one of which appears in profile in Figure l, and is secured thereto by suitable screws 63. It will be noted that an indentation 64 is provided in plate 55 for receiving the shaft 31 which, consequently, is supported only in the Widely spaced bearings 34, 35 which are advantageously disposed adjacent the operating arms 40, 4| to which the load is connected. It will be further noted that the gear 5| is disposed between the plate 55 and the removable casing portion 21. Accordingly, the shaft 31 and gear 5| are removable from the fixed casing portion 25 together with the removable casing portion 21 and the parts supported thereon simply by removing the arm 4| and permitting the shaft 31 to slip through the bearing 34.

Supported on the plate 55 and the removable casing portion 21 is a panel 55. The plate has a pair of extensions 66, 61. each having a turned up end provided with a threaded aperture for receiving a mounting screw 68 by means of which the panel 65 is secured to the plate 55. The removable casing portion 21 has an integrally formed ear 69 also provided with a threaded aperture for receiving a third mounting screw 88 by means of which the panel is secured to the casing portion 21.

Depending from the panel 65 are a pair of switches 18, 1| which may be identical, each having a resilient switch blade 12, 13, a movable contact 14, carried thereby, a fixed contact 18, 11 engageable by the movable contact, and a cam follower 18, 19 removably secured to the switch blades 12, 13, respectively. (See Figures 1, e, 6, 7 and l2.)

When the panel is in position the switches 18, 1| each depend on opposite sides of the gear 5|. The resilient blades 12 and 13 are self-biased so as to hold the followers 18 and 19 in engagement with cams 88 and 8| formed integrally with and extended axially of gearv 5|, as best seen in Figure l. The cams 88, 8l have formed therein diametrically opposed indentations 82, 83 respectively, which when radially aligned with the cam followers 18, 18 permit the same to move radially to openthe switches 18, 1| respectively. It will be understood that the motor 52 is a well known type capable of driving the shaft 31 in one direction, and that the switches i8 and 1| are inserted in the circuit for energizing the motor for the purpose of limiting the operation thereof to 188 per operation, each switch serving upon the opening thereof to terminate the operation. Such motors are conventionally used in control systems wherein each 180 position of the shaft 31 corresponds to a controlled condition of a furnace, for example, in which the check damper is opened and the draft damper is closed in one position and the check damper is closed and the draft damper is opened in the successive 180 position, the check and draft dampers being suitably connected to diametrically opposed operating arms such as arms 48, 4| shown in Figure 2. Accordingly, when the motor is stopped one switch is closed and the other is open, and when the motor is operating both switches are closed since the contacts are yieldably urged into engagement by the force of the cams 88, 8| on the cam followers 18, 19 respectively. As will hereinafter appear this force is ineffective to disengage the cam follower from the novel locking engagement with its supporting switch blade. To prevent the cam followers 18, 19 from sliding axially off of the cams 88, 8| and thereby becoming disengaged therefrom, an ear 84 on plate is bent at right angles and extends adjacent to the cam 88 and a boss 85 formed integrally with the removable casing portion 21 is extended adjacent to the cam 8|, as best shown in Figure 1.

Referring to Figures 6 and 12, it will be seen that the free end of each switch blade 12, 13 is bent into a substantially inverted V shape, and that squared apertures 86, 81 and 88 are formed therein at the free end, vertex, and attached end of the V respectively. The apertures 86, 88 receive hook-shaped tips 89, 98 formed integrally with each cam follower 18, 19, and the aperture 81 receives the portion of the cam follower between the tips. In assembling the cam follower and springfblade, the tip 98 is flrst lnserted in the aperture 88. Pressure is then applied forcing the free end .of the V to bend about the vertex thereof in a direction to close the open end of the V until the tip 89 snaps into the aperture 86 thereby locking the cam follower to the blade, the aperturey 81 serving to hold the same securely in locked engagement. It will be noted that the aperture 88 is elongated to accommodate the tip 98 as the cam follower moves longitudinally of the blade with the bending movement of the free end of the V about the vertex thereof. In removing the cam follower from the blade, the foregoing procedure must be repeated in reverse. In other words, the cam follower can be removed from the switch blade only by first applying a force to the tip of the switch blade in a direction to close the open end of the V. Accordingly, the cam followers cannot be removed by the action of the cams which action produces a flexing of the switch blades about their fixed ends only. The cam followers are formed of insulation material to prevent a now of current between the switches 18, 1| through the gear 5i when both switches are closed, as will be readily understood The switch blades 12, 18 may be formed of any suitable resilient metal or electrical conductive ma terial, preferably of Phosphor bronze.

Referring to Figure a plurality of terminals 8|, 82, 88, 98 and 85 are shown mounted on the panel which may be formed of any suitable insulating material such as Bakelite or the like. Each terminal includes a binding screw by means of which the necessary electrical conr nections for the motor operator may be made with the terminals. t will be noted that an indentation 98 is provided in the fixed casing portion 26 to receive the panel 85. The shape of indentation 88 corresponds substantially to the shape of panel 85. Thus, the panel, in effect, also serves as a part of the casing of the motor operator and electrical connections readily'may be made therewith without necessitating a disassembly of the casing.

The terminal 8| has fingers 88 formed integrally therewith which extend through the panel 65 to grip a conductor piece 81 disposed on the opposite side thereof, as best shown in Figure 4. The terminals 82, 88 andl 84 are sim ilarly secured to conductor pieces |88, |8| and |82, respectively. Terminal 85 is also secured similarly to contact piece |82.

Referring now to Figures ll and 1, it will be seen that the conductor contact pieces 81 and |82 serve as supports for the switch blades 12 and 13, respectively, and that they have contact portions |83, |88, respectively, which are received in indentations formed in a plate of insulating material |88 secured to the panel 85 for the purpose of holding the conductor pieces 91 and |82 securely in position. lThe conductor piece |88 similarly has a contact portion |88 which is also received in an indentation formed in the insulation plate H85. The fixed contacts 16, 11 are supported on a common conductor piece |81 mounted on the insulation plate |85 and secured therewith to the panel 8S by means of rivets |88. The manual control lever 88! hereinbefore referred to, is secured for rotation with a pin |89 which is journalled in the Contact piece |81. The pin also carries a resilient switch blade ||8 which resiliently engages the conductor piece |81, the blade H8 having turned down fingers I| which serve for this purpose. The blade ||8 is engag'eable with the contact portions |83, |84,

and selectively when the manual control lever is adjusted in accordance with the legends on plate 25. A circuit for energizing. the motor 52 may be completed by an external controller, .such as a thermostat, for example, through either of the switches 10, 1| lwhen the lever 24 is adjusted to the automatic positionthereby moving blade ||0 into engagement with Contact portion |06. A circuit is completed through the .switch when lever 2 is adjusted to the closed position. A circuit is completed through the switch 1| when lever 24 is adjusted to the open position. These circuits will be hereinafter explained in connection with the operation of the motor operator as utilized in a heating system.

The conductor pieces 91 and |0| have turned up portions ||2 and ||3 comprising terminals each of which carries a binding screw by means of which the ends H4, IE5 of motor windings ||6, ||1 are secured to the conductor pieces 91 and I0 I respectively.

Referring to Figure l, it will be seen that the windings ||5 and ||1 are conveniently arranged on the motor core I I8. As shown, the core I IB is of the window type in which the field coils are wound on pole pieces |I8a, which together with the armature comprise a central magnetic path for the motor.

The windings ||6, ||1 are series connected as is clearly shown in Figures 9, 13 and 15 and each comprises many turns of wire. A piece of tubular insulation I I9 is employed to cover the joined terminals of the two windings. Each winding H6, ||1 is wound upon an insulation piece ||9a, which is `folded about the pole piece ||8a as is best shown in Figure 15. The end insulation pieces are positioned over the folded insulation pieces ||9a, as is best shown in Figure 15, closely adjacent the ends thereof to prevent their unfolding and thus serve to hold the same in position on the core. At least one insulation piece |20 of each winding is provided with two pairs of apertures |2| which are extended to an edge of the insulation piece as best shown in Figure 8. Adjacent the free end of each' Winding I I6, I |1, the wire is wound with one or more turns about the portion of the insulation piece |20 defined by the apertures I2 I. The projecting portions of the wire are covered with pieces of tubular insulation |I9, and the ends ||4, ||5 thereof are secured to the terminals ||2 and ||3 as previously described. Thus, by this arrangement the windings are securely held upon the motor core IIB and but two internal connections are required to electrically connect the motor with the panel thereby promoting economy of construction and facilitating ease of assembly of the motor operator parts. Moreover, since the panel 65 and motor 52 are both supported on the removable casing portion 21, they may be removed. therewith from the fixed casing portion 26 without necessitating the severance of electrical connections therebetween which is obviously a decided advantage in disassembling the operator for purposes of inspection and repair.

From the foregoing, it is apparent that the casing portions 25, 21 may be advantageously provided in the form of castings, th'ereby obviating a time consuming assembly of a plurality of parts. Each casting comprises, besides the casing itself, integrally formed parts which perform other functions, as for example, the posts 62, etc. The casing portions 26, 21 are preferably cast, for example, of zinc or other suitable metals, but may be moulded of Bakelite or other suitable plastics, if so desired. While castings are preferred asbest suited for the purposes of this invention, their use is not indispensable, and other means of fabrication well known in the art may be resorted to if desired.

Referring now to Figure 9, the motor operator 20 is schematically shown as employed in a heating system, th'e parts previously described being designated by the same reference characters.

The numeral |22 generally designates a transformer having a primary winding |23 connected to asuitable source of A. C. power, not shown, and a secondary winding |24 for energizing the motor 52.

The numeral |25 `generally designates a thermostat, which asv shown, is of a conventional single-pole double-throw type, comprising a bimetallic strip |26, a. switch blade |21 secured thereto and movable thereby, a movable contact |28 carried by the blade |21, and a pair of fixed contacts |29`and |30 engageable by the movable contact. It will be understood that the thermostat is situated in a space heated by a furnace,

' the draft and check dampers of which are connected to the operator arms 40 and 4| respectively, and controlled by the motor operator 20.

In the operation of Figure 9, with the parts in their full line positions as shown, the switch blade ||0 is adjusted for automatic operation in which position the thermostat |25 is in control of the motor 52, the operator arm 40 is in a down position in which' position the draft damper is closed, the arm 4| is in a raised position in which the check damper is open, and the switch 10 is open.

When the temperature in the space drops, the bimetallic strip |26 moves the blade |21 in the direction of the legend C and the contact |20 engages the contact |30 completing a circuit to the motor 52 as follows: from secondary winding |24, through a conductor |3I, terminal 93, conductor piece |0|, motor terminal |I3, winding lead wire |I5,windings ||1, ||6, winding lead wire I4, motor terminal |2, conductor piece 91, terminal 9|, a conductor |32, contacts |30, |28, switch' blade |21, bimetallic strip |26, a conductor |33, terminal 92, conductor piece |00, contact portion |06, switch blade I0, conductor piece |01, switch 1|, switch blade 13, conductor piece |02, terminal 94, and throughaconductor |34 back to secondary winding |24.

The motor 52 then drives the shaft 31 for one half a revolution whereupon the switch 1| is opened and terminates further operation. In this position the operating arms 40 and 4| occupy their dotted line positions which correspond to a controlled condition of the furnace in which the check damper is closed and lthe draft damper is open. The furnace then operates to supply heat to the space until the temperature has reached a predetermined value as determined by the differential of the thermostat |25.` The strip |26 then movesthe blade |21 in the direction of legend H and Contact |28 engages Contact |29.

A circuit is then completed to motor 52 as follows: from secondary |24, through' conductor |3I, terminal 93, conductor piece |0|, motor terminal ||3, winding lead wire ||5,` windings ||1, ||6, winding lead wire |I4, motor terminal ||2, conductor piecel 91, switch blade 12, switch 10, conductor piece |01, switch blade ||0, contact portion |06, conductor piece |00, terminal 92, conductor |33, strip |26, blade |21, contacts |28, |29, a conductor |35, terminal 95, conductor piece |02,

terminal 94, and through conductor |34 back to secondary winding |24. The motor 52 then operates for another one half a revolution of the shaft 31 thus returning the arms 40 and 4| to their initial full line positions.

At a time when the draft damper `is closed and the check damper is open, it may be desired to open the draft damper and close the check damper independently of the thermostat |25. For example, such a movementl of the dampers might be needed during stoking of the furnace. In order to do this, the control lever 24 may be moved to the open position which completes a circuit to the motor as follows: from secondary winding |24 through |3|, terminal 93, conductor piece motor terminal ||3, winding lead wire ||5, windings ||1, ||6, winding lead wire |l4, motor terminal ||2, conductor piece 91, contact portion |03, switch blade H0, conductor piece |01, switch 1|, conductor piece |02, terminal 94, and conductor |34 back to secondary winding |24. As previously pointed out, the motor then operates until the switch 1| opens which corresponds to the draft damper open, check damperclosed condition.

On the other hand, at a time when the draft damper is open and the check damper is closed,` it may be desired to close the draft damper and open the check damper. If so, the control lever 24 may be moved to the closed position which completes a circuit to motor 52 as follows: from secondary winding |24, through conductor |3|, terminal 93, conductor piece |0|, motor terminal ||3, winding lead wire IE5, winding ||1, ||6, winding lead wire |l4, motor terminal ||2, conductor piece 91, switch 10, conductor piece |01, switch blade H0, contact portion |04, contact piece |02, terminal 94, and conductor |34 back to secondary winding |24. As previously pointed out, the motor then operates until the switch 10 opens which corresponds to the draft damper closed, check damper open condition.

Figures l0, 1l and l2, show a switch assembly mounted on a panel |36 which is a modification oi' the panel 65 and the switch assembly shown in Figures l, 2, 4 and 7. These panel and switch assemblies are made interchangeable in order that the motor operator 20 may be adapted to different control circuits.

As best shown in Figures ll and 12, additional switches |31, |38 are provided in the plane of switches 10, 1| respectively, being mounted on the panel |36 in such manner that their respective cam followers |39, |40 engage the indentations 82, 63 approximately 30Q behind the cam followers 19, 19 of switches 10, 1| respectively. Accordingly, taking the angular position of gear 5| in which switch 19 is open as a datum, it will be understood that the switch |33 will be opened after 150, switch 1| after 180, switch |31 after 330, and switch 10 opened again after 360 of rota-tion of gear 5|. The cam followers |39, |40 are formed of insulation material and are of a suitable angular configuration as illustrated in Figure l2, being provided with hooked tips for engagement with their respective switch blades lil, 42, as in the case of the connection between cam followers 16, 19 and their respective switch blades 12. 13. The switches |31, |38 further comprise movable contacts |43, |44 carried by switch blades Ml, |43 and engageable with xed contacts |45, |46, respectively.

The switch blades 13, |42 are supported on a common conductor piece |41 as shown in Figures l1 and l2, which is secured to the panel |36 by the terminal |48 in the same manner as previously described in connection with panel 65. The xed contact 11 of switch 1| is, in this case, supported on a conductor piece |49 which also serves as a support for fixed contact |45 of switch |31, the conductor piece |49 being secured to panel |36 by a terminal |50. The switch blade. |4| of switch |31 is supported on a conductor piece |5| which is secured to panel |36 by the terminals |52, |53, and |54.- The iixed contact 16 of switch 10 is supported on a conductor piece |55 which also serves as a support for the fixed contact |46 of switch |38, the conductor piece |55v being secured to the panel |36 by the terminals |56 and |51. The switch blade 12, as in the' case of panel 65, is supported on the conductorpiece 91 which has the turned up portion I|2 for electrical connection with the motor 52 aspreviously explained. Conductor piece 91, also as in the case of panel 65, is secured to panel |36 by the terminal 9|. The conductor piece |0|, which has the turned up portion ||3 as used on panel65 for making the other electrical connection with the motor 52, is similarly used on panel |36. Also, conductor piece |0| is similarly secured to panel |36 by the terminal 93.

From the foregoing it may be seen that the switches 10, |38, 1|, 31 are connected in series as follows: beginning at terminal 9|, through conductor piece 91, switch blade12, contacts 14, 16, conductor piece |55, contacts |46, |44, switch blade |42, conductor piece |41, switch blade 13, contacts 15, 11, conductor piece |49, contacts |45,

|43, switch blade |41, conductor piece |5| to terminal |52.

As seen in Figures 1l and l2, the conductor pieces |49 and |55 have inwardly turned ears |62, |63, respectively, which extend adjacent to the cam followers |39,r |40 respectively, and serve to prevent' the same from moving axially off of the cams and 8|, respectively.

Referring to Figures 1, 3, and 4, the numeral |64 generally designates an auxiliary switch of the self-return type in which a greater force is required to actuate the switch than to maintain it in its actuated position. Switch |64 maybe substantially of the type as described in the copending application of Albert E. Baak, Serial No. 307,991, led December '1, 1939.

As shown in Figure 3, switch |64 is conveniently mounted on the iixed casing portion 26 by means of suitable screws |65, and has an actuating button |66v projecting through an aperture |61 provided in ythe fixed casing portion.

The button |66 is actuated by alever generally designated by the numeral |68 which is suitably pivotally supported on a ypivot pin |69 secured to a post 62. The lever |68 comprises a rigid portion |10 having shaped on its free end a curved portion |1| which is yieldablyforced into engagement with a cam |12, suitably secured to the operator shaft 31, by a resilient spring blade |13 riveted to the lever portion |10 and engageable with the actuating button I 66. i

The disposition of cam |12 on shaft 31 is .such that it bears a denite circumferentially displaced relationwithrespect to the indentations 02,' 83 in gear 5|. Again taking the angular position of shaft 31, in which switch 10 is in its open position as a datum, the follower portion |1| of lever |68 engages the leading edge |14 of cam |12 after theshaft 31 has rotated approximately and engages the vtrailing edge |15 after approximately 345 rotation of shaft 31.

With the foregoing arrangement it will be apparent 'that the switch |84 Awill be actuated after 180 of movement of shaft `31 in which position the `switch 1| is opened. It will still-be actuated after 330of movement in which case the switch |31 is opened.

The additional switches |31, |38 and the switch |84 may be used for the purpose of providing a cooperative action between the controls of a'furnace, for example, the check and draft da-mpers of a `hot air furnace and a-fan for circulating the air warmed by the furnace, as will hereinafter appear in` a description of the operation of the modiedform `of the motor operator vas utilized inlsuch a heating system.

`Referring now to Figure 13, the modified form of the motor operator 20a appears schematically as a part of a condition control system which is substantially of the type vdescribed'and claimed in the copending application to John Kriechbaum, Serial No. 432,983, ledMa-rch 2, 1942. The same reference characters are used in this figure to designate the parts as previously described.

The numeral |16 generally designates a hotair furnace which comprises theusual combustion chamber |11, air enclosure or bonnet |18 .partially surrounding the combustion chamber, draft damper |19 associated with the` combustion chamber, and check damper |80 suitablycarried by the-stack |8| inthe usual manner.

"Leading from the bonnet |18'atthe top of the furnace-is a supply duct' |82 which communicateg with aspace |83 to which air warmed in the bonnet is -to be supplied. A circulating fan |84 having an operating motor |85 is provided for` drawing air from the space |83 through a return duct |86 and forcing air through the bonnet |18 and supplyduct |82 intothe space |83.

Operating arms L40, 4| are shown connected to the draft and check dempers respectively'by means of chains |81, |88 which may be'trained over a convenient number of pulleys |89.

The numeral |90 generally'designates a transformer which comprises aprimary winding |9| connected to lines |92, |93 which maybe supplied by'any suitable source, not shown, and a secondary winding |94 for energizing the'motor 52. Switch |64 controls the energization'of fan motor |85, the circuit to the motor being as follows: from line |92 throughY a conductor |95, switch |64, a. conductor |96, motor |95, anda conductor |91 back to line |83.

`As previously pointed out,tthe switches 1 I, |38, 10, and |31 are connected in series forming a part of a simple circuit for energizing the motor.52, `'each switch serving upon the openingthereof to terminate operation of the motorandcnly one switch being open at any instant.

yIn Figure 13,` for the sakeof simplifying the illustration, the switches 10, |31, 1|, |38 f are schematically shown as being actuated by separate cams 80, 80a, 8|, 8|a having indentations 82, 82a, 83, 83a respectively. It will be understood that cams 80 and 80a together correspond to cam 80 of Figure 1, and that cams 8| and`8|a together correspond to cami8| of Figure 1. The clrcumferentially displaced relation of the switches with respect to the indentations proW vides the same sequence of the opening ofthe switches, however, as previously described, as will readily be understood.

For initiating operation of the control motor 52 t'o adjust shaft 31 to a position corresponding to a particular controlled condition of the furnace |16 and circulating fan |84, a plurality of circuits are provided for shunting one or more of the switches so as to cause operation of the motorA 52 until the particular switch is opened which provides a position of shaft 31 corresponding to the controlled condition desired. The various shunting circuits required to initiate the movement of the control motor 52 are established by a pair of thermostatic means |98 and |99 responsive to variations in the temperature of l0 thespace |83 andfurnace |16, respectively.

As shown in the drawings the thermostatic means |98 is a conventional single pole, double throw thermostat which comprises a bimetallic strip 200` to which is suitably attached a Contact blade..20|. `The contact blade 20| carries a contact 202 which is engageable with a pair of fixed contacts 203 and 204.

Asshownin the drawings, the thermostatic means |99 is a conventional bonnet thermostat Q0 comprising a helical bimetallic strip 205 which is inserted into the bonnet |18 of the furnace |16. The strip 205 actuates a rod 206 in the usual manner, the rod 206 in turn, actuating a pair of mercury switches 201 and 208. The switch 201 comprises a glass envelope 209 and two pairs of electrodes 2|0, 2|| and 2|2, 2|3, the electrodes Zlfland 2|2 being jointed to provide a commcnterminal. Each pair of electrodes may be electrically connected by. a globule of mercury 2|4 sealed in the envelope in the usual manner.

The switch 208 similarly comprises a glass envelope 2 l5 and. a globule of mercury 2|6 for electrioally connecting a pair of electrodes 2|1 and 2|8.

As shown, the switch 201 is slightly inclined with the horizontal in which position the elec trodes12|2 and'2l3 are electrically connected, the electrodes 2|0 and 2| becoming electrically connected upon a rise in temperature of the bonnet Alo |18 toa predetermined value. The switch 208 is `further inclined in the same direction for the purpose of connecting its electrodes 2|1 and 2|8 aty a considerably higher bonnet temperature than that at which electrodes 2|0 and 2|| bei" come connected. The switch 208 constitutes a limitcontrol for preventing continued operation of `the furnace .at an unsafely high value, as will hereinafter appear.

In the operation of Figure 13, with the parts in 5') their full line positions as shown, arm 40 is in the downv position which provides a closed position of the draft damper |19, arm 4| is in an up position which provides an open position of the check damper |80, switch 10 is open and motor 52 is therefore stopped and fan switch |64 is open and fan motor |85 is therefore stopped.-

Assuming now that the temperature in the space |83 drops below the value which the system is set to maintain, the blade 20| then moves 50 to the left in the direction of legend C and contact'202 engages fixed Contact 204 which estabflishesa circuit shunting switch 10 and energizing the motor 52 as follows: from secondary winding. |94 through a conductor 2|9, terminal (35 93, contact piece |0|, motor terminal |51, winding lead wire |I5, windings H1, H0, winding lead wire H4, motor terminal H2, conductor `piece 91, `terminal .05, a conductor 220, contacts 204, 2073, switch blade 20|, strip 200, a conductor 22|, ter- `minal |50, conductor piece |55, switch |38, conductor piece |41, switch 1|, conductor piece |40, switch |31, conductor piece |51, terminal |52, and `a conductor 222 back to secondary winding |94.

.Motor 52thcnopcrates until switch |38 is opened land the arm 40 `moves to the dotted line position marked 150 in which position draft damper |19 is in its open position as indicated by the dotted lines. 'I he arm 4| simultaneously moves to the dotted line position marked 150 in which position the check damper |80 is closed as indicated by the dotted line position. Since this operation produces but 150 of rotation of shaft 31, the leading edge of cam |12 does not engage the lever |68 to actuate the switch |54. Consequently, the fan |84 is not set into operation at this time.

The furnace |15 then operates at an increased capacity and the temperature in the bonnet rises to a point where the switch 201 is tilted by the biinetallic element 205 in a counterclockwise direction to such an extent that the electrodes 2|0 and 2II are electrically connected. This estab-- lishes a circuit shunting the switch |38 and energizing the motor 52. This circuit may be traced as follows: from secondary winding |94 through conductor ZIS, terminal 93, conductor piece motor terminal ||3, winding lead wire |I5, motor windings I |1, i6, winding lead wire I I4, motor terminal I|2, conductor piece 91, switch 10, conductor piece 55, terminal |51, a conductor 223, electrodes 2| I, 2I0, a conductor 224, termL nal |48, conductor piece |41, switch 1 I, conductor piece |49, switch |31, conductor piece |5|, terminal |52, and conductor 222 back to secondary winding |04. Motor 52 then operates until switch 1| is opened. During this operation, motor 52 drives arms 40 and 4| to the dotted line positions marked 180. The draft damper |10 and check damper |80 remain substantially in their dotted line positions to which theywere driven on the previous operation of the motor. This operation of motor 52 also drives the leading edge |14 of cam |12 into engagement with the lever |68 which actuates the switch |64 thereby energizing the fan motor |85 and driving the fan |04 to supply the warmed air to the space |83.

When the temperature in the space |83 has reached a predetermined value as determined by the-differential of the'thermostat |98, `the contact 202 engages the fixed contact 203 which establishes a circuit shunting all of the switches except switch 10. This circuit energi'zes motor 52 and may be traced Ias follows: from secondary winding |94 through conductor 2|9, terminal 93, conductor piece |0 l, motor terminall I3, winding lead wire I5, motor windings I I1, I I6, winding lead wire I|47 motor terminal I I2, conductor piece 91, switch 10, conductor piece |55, terminal |56, conductor 22|, strip 200, switch blade 20|, contacts 202, 203, a conductor 225, terminal |53, contact piece |5|, terminal |52, and conductor 222 back to secondary winding |94. Motor 52 then operates until switch isr opened in which position the parts again occupy their full line positions and one cycle of operation has been completed. y

Assume that shaft 31 has been driven to its 180 position wherein, as previously explained, switch 1| is open, draft damper |19 is open, the check damper |80 is closed, and the circulating fan |84 is operating. Assume further that the temperature in the bonnet rises to an unsafely high value before the space thermostat has become satisfied. Under such conditions the switch 203 will be tilted by the bimetallic element 205 to a position in which the electrodes 2I1 and 2| 8 are electrically connected thereby establishing an energizing circuit forl motor 52 which shunts switches |33 and 1| and may be traced as follows: from secondary Winding |94 through conductor 2|9, terminal 93, conductor piece |0I, motor terminal I|3, winding lead wire I5, motor windings ||1, IIE, winding lead wire llt, motor terminal H2, conductor piece 01, switch 10, conductor piece |55, terminal |51, Conductor 223, a conductor 220, electrodes 2|1, 2.!3, a conductor 221, terminal |50, contact piece |49, switch |31, Contact piece |5|, terminal |52, and conductor 222 back to secondary winding |04. Moto-r 52 then operates until switch |31 is opened. lll'his operation of motor 52 drives arms 40 and 4| to the dotted line position marked 330 in which position the draft damper |10 is closed and check damper |00 is open, each occupying its respective full line position. rEhe cam |12, however, is still in a position in which switch |54 is closed and the fan motor. E05 continues to operate. The circulating fan |84, then, continues to supply warmed air to the space |03 until the thermostat |98 becomes satised and shunts all of the switches except switch 10. However, if the bonnet |18 cools before the space thermostat |98 becomes satised, the switch 201 then assumes the position, as shown, in which the electrodes 2|2 and 2|3 are electrically connected. This completes a circuit for energizing motor which shunts switches 1| and |31 and may be traced as follows: from secondary Winding |04 through conductor 2|5, terminal 93, conductor piece lll, motor terminal I3, winding lead wire I i5, motor windings !|1, IIO, winding lead wire H4, motor terminal |l2, conductor piece 91, switch 10, conductor piece |55, switch |33, conductor piece |41. terminal |48, conductor 224, electrodes 2|2, 2| a conductor 22B, terminal |54, contact piece |5|, terminal |52, and conductor 222 back to secondary winding |04. The motor 52 then operates until switch 10 is opened thereby restoring the system. to its original condition as previously described in which the various parts occupy their full line positions as seen in Figure 13,

Assuming aga-in that arms i0 and 4| are in their 180 yposition in which switch 1| is open, and assume further that the temperature of the bounet drops before the room thermostat |08 ben comes satisfied. It should be here pointed out that this condition is extremely unusual, since, with the draft damper open and the check damper closed, the furnace usually has suiiicient capacity to satisfy ordinary demands. However, in such cases in which the furnace might fail to function properly as. for example, where re-fueling is negu lected or the fuel supply is depleted, or other conditions in which the furnace operates at rdecreased capacity, it is desirable to shut off the circulating fan to prevent a circulation. of cold air to the space. Under such a condition the switch 201 assumes the position. as shown, in which the electrodes 2|2 and 2|3 are electrically connected. This completes.the circuit for energizing motor 52 which shunts switches 1| andll as traced in the preceding paragraph. Assuming that the thermostat |98 is not calling for heat, in other words, the contact 202 is not engaging the contact 204, the motor 52 will operate until the switch 10 is opened and the system is restored to its original condition as previously described.

Assume, however, that the roo-rn. thermostat l 0|? is still calling for heat when the bonnet cools her cause of continuous operation of the fan |04 for too long a time, such as might be the case under extrem@ operating conditions as pointed out here inabove. Insuch case the switch 201 shunts the Switches 1| and |31 and the thermostat |00 shunts switch 10 since the contacts 202 and |204 are in engagement. The motor 52 thenoperates until the switch |38 is opened, which as previously described, corresponds to the 150 position of shaft 31, in which the draft damper |19 is opened, the check damper |80 is closed and the circulating fan |84 is inoperative. When the bonnet becomes sufficiently warm to close contacts 2|0 and 2|| of the switch 201, thereby energizing the motor 52 to close the switch |64, the circulating fan will again be operated until the thermostat |98 is satisfied, thus repeating the cycle.

Assume a condition in which the air in the bonnet has been warmed to such an extent that the switch 201 is tilted to a position in which the electrodesl RIG and 2li are electrically connected, and assume further that the shaft 31 is in its 0 position wherein switch 1|) is open, Under such conditions, when the thermostat |83 calls for heat, engagement of contacts 202 and204 shunts the switch 10, and since the switch 201 shunts the switch |38, the motor 52 operates directly to the 180 position in which switch 7| is opened, the switch |64 is closed, and the fan im operates to supply warmed air to the space |33.

-From the foregoing it is obvious that I have provided a motor operator of unusual utility which is well adapted for the purposes intended. Moreover, while I have selected but two embodiments thereof asbest being illustrative of the principles involved, I do not wish to be strictly limited thereto and contemplate all such alterations, additions, omissions, and substitutions as would naturally occur to those skilled in the art without departing from the spirit or scope of the invention as deiined by the appended claims.

I claim as my invention:

l. A motor operator comprising a casing having a iixed portion and a portion removably secured thereto, an operating shaft journalled in part in said fixed and in `part in said removable casing portion, a motor and gear train for driving said shaft, means for supporting said motor and gear train on said removable casing portion in drivable engagement with said shaft, a panel for electrical connections with said motor, and means for mounting said panel on said removable casing portion so as t0 be removable therewith from said fixed casing portion together with said motor and gear train.

2. A motor operator comprising a casing having` a xed portion and a portion removably secured thereto, an operating shaft, a iirst journal therefor in said fixed portion, a second journal there-- for in said removable portion, means on said fixed and removable casing portions for providing axial alignment of said journals, a motor and gear train for driving said shaft, means for supporting said motor and gear train on said removable casing portion in drivable engagement with said shaft, a panel for electrical connections with said motor, and means for mounting said panel on said removable casing portion so as to be removable therewith from said fixed casing portion together with said motor and gear train.

3. A motor operator comprising a casing having a fixed portion and a portion removably secured thereto, an operating shaft journalled in part in said fixed and in part in said removable casing portion, a motor and gear train for drivingsaid shaft, means for supporting said motor and gear train on said removable casing portion in drivable engagement with said shaft, panel for electrical connections with said motor, means for mounting,r said panel on said removable casing portion so as to be removable therewith from said fixed casing portion together withsaid motor and gear train. and -rneans lon said fixed casing portion for mounting said casing to a suitable support therefor.

4. 4A motor operator comprising a casing having a fixed portion and a portion removably secured thereto,an operating shaft, a first journal there-- for in said iixed portion, a second journal therefor in said removable portion, said operating shaft projecting outwardly of each said journal and having operating arms removably secured thereto, a motor and gear train for driving said shaft, means for supporting said motor and gear train on said removable casing portion in drivable engagement with saidshaft, a panel for electrical connections with said motor. and means for mounting said panel on said removable portion so as to be removable therewith from said fixed casing portion together with said motor and gear train upon removal of said operating arm adjacent said journal in said fixed casing portion.

5. A motor operator comprising an electric motor and a casing therefor, said casing comprising a fxedportion, and a portion removably secured thereto, a panel for electrical connections with. said motor, said panel comprising a part of the removable portion of the casing and said motor being ymounted on said removable casing portion for removal therewith from said fixed casing portion, said fixed casing portion being shaped to interttingly engage said panel when said portionsare secured together so that the fixed portion together with the removable portion and panel form a complete casing for the motor operator.

6. In an electrical device, a magnetizable core, a winding comprising a number of turns of wire mounted on said core, a casing for said winding and core, a panel secured to said casing electrically connected to the end of said winding, and means abutting an end of said winding to hold the turns of wire in position on said core, said means cooperating with `the end of the winding connected to said panel to prevent loosening of :the turns of said Winding.

'1. A motor operator comprising a casing having a fixed portion and a portion removably secured thereto, an operating shaft journalled in part in said fixed and in part in said removable casing portion, a plate secured to said removable casing portion in spaced relation therewith, a motor mounted on said plate, a gear train mounted for rotation between said plate and removablecasing portion in drivable relation with said motor and said shaft, and a panel for electrical connections with said motor, said panel being supported on said plate and said removable casing portion so as to be removable therewith from said fixed casing portion together with said motor and gear train.

8. A motor operator comprising a casing having a fixed portion and a portion removably secured thereto, a shaft journalled in said casing, a motor and gear train supported on said removable casing portion in drivable relation with said shaft, a panel mounted on said removable casing portion, switch means depended from said panel, means on said shaft engageable with said switch means for actuating the switch means, and circuit means including said motor, switch means, and a source of power for energizing said motor, said switch means serving upon the opening thereof to terminate operation of said motor.

9. A -motor operator comprising a casing having a fixed portion and a portion removably secured thereto, a shaft journalled in said casing, a motor and gear train supported on said removable casing portion in drivable relation with said shaft, a panel mounted on said removable casing portion, switch means depended from said panel, means on said shaft engageable with said switch means for actuating the switch means, manually operable switch means carried by said panel, and circuit means including said motor, switch means, manual switch means, and a source of power for energizing said motor, said first switch means serving upon the opening thereof to terminate operation of said motor, and said manual switch means being operable to complete a circuit for initiating operation of lsaid motor independently of said switch means.

10. In a motor operator, an electric motor, a casing therefor, a shaft journalled in said casing, driving connections between said motor and said shaft including a member secured to the shaft, said member having an integrally formed substantially cylindrical portion extended to each side thereof, said cylindrical portion having peripheral indentations formed therein, a panel secured to said casing, and a plurality of switches for controlling the energization of said motor depended from said panel and engageable with said cylindrical portions, said switches being so arranged with respect to said indentations as to be actuated in sequence thereby, each said switch serving upon the opening thereof to terminate operation of said motor.

able casing portion in spaced relation therewith, a motor mounted on said plate, driving connections between said motor and said shaft including a member secured to the shaft, said member having cam means formed integrally therewith and extended axially to each side thereof, a panel secured to said casing, a plurality of switch means depended from said -panel into engagement with saidl cam means to be actuated thereby, each axially extendedv cam portion having in engagement therewith at least one of said plurality of switch means, said member being disposed between said plate and said removable casing portion, and means depended from said plate and said removable casing portion for holding said switch means in engagement with said cam means.

12. A motor operator comprising a casing having a fixed portion and a portion removably secured thereto, an operating shaft journalled in par-t in said fixed and in part in said removable casing portion, a plate secured to said removable casing portion in spaced relation therewith, a motor mounted on said plate, driving connections between said motor and said shaft including a member secured to the shaft, said member having cam means formed integrally therewith and extended -axially to each side thereof, a panel secured to said casing, and a plurality of switch means depended from said panel into engagement with said cam means to be actuated thereby, each axially extended cam portion having in engagement therewith atleast one of said plurality of switch means, said member being disposed between said plate and said removable casing portion.

WALTER E. EDELMAN. 

